JSON import bug

Daniel_Webb · January 22, 2024, 10:55pm

Ignition 8.1.28 (b2023060110)
Script in button Event Handlers -> action -> actionPerformed:

import json
json.dumps({'a': 'test'})

Pushing button results in:

16:51:54.818 [AWT-EventQueue-0] ERROR com.inductiveautomation.ignition.client.util.gui.ErrorUtil - <HTML>Error executing script for event:&nbsp;<code><b>actionPerformed</b></code><BR>on component:&nbsp;<code><b>TestButton 1</b></code>.
com.inductiveautomation.ignition.common.script.JythonExecException: Traceback (most recent call last):
  File "<event:actionPerformed>", line 1, in <module>
  File "C:\Users\aedmw\.ignition\cache\gwlocalhost_8088\C0\pylib\json\__init__.py", line 108, in <module>
    from .decoder import JSONDecoder
  File "C:\Users\aedmw\.ignition\cache\gwlocalhost_8088\C0\pylib\json\decoder.py", line 24, in <module>
    NaN, PosInf, NegInf = _floatconstants()
  File "C:\Users\aedmw\.ignition\cache\gwlocalhost_8088\C0\pylib\json\decoder.py", line 18, in _floatconstants
    _BYTES = '7FF80000000000007FF0000000000000'.decode('hex')
  File "C:\Users\aedmw\.ignition\cache\gwlocalhost_8088\C0\pylib\encodings\__init__.py", line 142, in search_function
    raise CodecRegistryError,\
encodings.CodecRegistryError: incompatible codecs in module "encodings.hex_codec" (C:\Users\aedmw\.ignition\cache\gwlocalhost_8088\C0\pylib\encodings\hex_codec.py)

	at org.python.core.PyException.doRaise(PyException.java:211)
	at org.python.core.Py.makeException(Py.java:1638)
	at org.python.core.Py.makeException(Py.java:1642)
	at encodings$py.search_function$3(C:\Users\aedmw\.ignition\cache\gwlocalhost_8088\C0\pylib\encodings\__init__.py:164)
	at encodings$py.call_function(C:\Users\aedmw\.ignition\cache\gwlocalhost_8088\C0\pylib\encodings\__init__.py)
	at org.python.core.PyTableCode.call(PyTableCode.java:173)
	at org.python.core.PyBaseCode.call(PyBaseCode.java:134)
	at org.python.core.PyFunction.__call__(PyFunction.java:416)
	at org.python.core.PyFunction.__call__(PyFunction.java:411)
	at org.python.core.codecs$CodecState.lookup(codecs.java:1706)
	at org.python.core.codecs.lookup(codecs.java:58)
	at org.python.core.codecs.decode(codecs.java:98)
	at org.python.core.PyString.decode(PyString.java:4015)
	at org.python.core.PyString.str_decode(PyString.java:4023)
	at org.python.core.PyString$str_decode_exposer.__call__(Unknown Source)
	at org.python.core.PyObject.__call__(PyObject.java:461)
	at org.python.core.PyObject.__call__(PyObject.java:465)
	at json.decoder$py._floatconstants$1(C:\Users\aedmw\.ignition\cache\gwlocalhost_8088\C0\pylib\json\decoder.py:22)
	at json.decoder$py.call_function(C:\Users\aedmw\.ignition\cache\gwlocalhost_8088\C0\pylib\json\decoder.py)
	at org.python.core.PyTableCode.call(PyTableCode.java:173)
	at org.python.core.PyBaseCode.call(PyBaseCode.java:119)
	at org.python.core.PyFunction.__call__(PyFunction.java:406)
	at json.decoder$py.f$0(C:\Users\aedmw\.ignition\cache\gwlocalhost_8088\C0\pylib\json\decoder.py:273)
	at json.decoder$py.call_function(C:\Users\aedmw\.ignition\cache\gwlocalhost_8088\C0\pylib\json\decoder.py)
	at org.python.core.PyTableCode.call(PyTableCode.java:173)
	at org.python.core.PyCode.call(PyCode.java:18)
	at org.python.core.imp.createFromCode(imp.java:630)
	at org.python.core.imp.createFromPyClass(imp.java:312)
	at org.python.core.imp.createFromPyClass(imp.java:255)
	at org.python.core.imp.loadFromSource(imp.java:929)
	at org.python.core.imp.find_module(imp.java:769)
	at org.python.core.PyModule.findSubModule(PyModule.java:140)
	at org.python.core.PyModule.impAttr(PyModule.java:107)
	at org.python.core.imp.import_next(imp.java:1161)
	at org.python.core.imp.import_module_level(imp.java:1350)
	at org.python.core.imp.importName(imp.java:1528)
	at org.python.core.ImportFunction.__call__(__builtin__.java:1285)
	at org.python.core.PyObject.__call__(PyObject.java:433)
	at org.python.core.__builtin__.__import__(__builtin__.java:1232)
	at org.python.core.imp.importFromAs(imp.java:1620)
	at org.python.core.imp.importFrom(imp.java:1595)
	at json$py.f$0(C:\Users\aedmw\.ignition\cache\gwlocalhost_8088\C0\pylib\json\__init__.py:293)
	at json$py.call_function(C:\Users\aedmw\.ignition\cache\gwlocalhost_8088\C0\pylib\json\__init__.py)
	at org.python.core.PyTableCode.call(PyTableCode.java:173)
	at org.python.core.PyCode.call(PyCode.java:18)
	at org.python.core.imp.createFromCode(imp.java:630)
	at org.python.core.imp.createFromPyClass(imp.java:312)
	at org.python.core.imp.createFromPyClass(imp.java:255)
	at org.python.core.imp.loadFromSource(imp.java:929)
	at org.python.core.imp.find_module(imp.java:769)
	at org.python.core.imp.import_next(imp.java:1158)
	at org.python.core.imp.import_module_level(imp.java:1350)
	at org.python.core.imp.importName(imp.java:1528)
	at org.python.core.ImportFunction.__call__(__builtin__.java:1285)
	at org.python.core.PyObject.__call__(PyObject.java:433)
	at org.python.core.__builtin__.__import__(__builtin__.java:1232)
	at org.python.core.imp.importOne(imp.java:1547)
	at org.python.pycode._pyx27.f$0(<event:actionPerformed>:2)
	at org.python.pycode._pyx27.call_function(<event:actionPerformed>)
	at org.python.core.PyTableCode.call(PyTableCode.java:173)
	at org.python.core.PyCode.call(PyCode.java:18)
	at org.python.core.Py.runCode(Py.java:1687)
	at com.inductiveautomation.ignition.common.script.ScriptManager.runCode(ScriptManager.java:803)
	at com.inductiveautomation.factorypmi.application.binding.action.ActionAdapter.runActions(ActionAdapter.java:207)
	at com.inductiveautomation.factorypmi.application.binding.action.ActionAdapter.invoke(ActionAdapter.java:300)
	at com.inductiveautomation.factorypmi.application.binding.action.RelayInvocationHandler.invoke(RelayInvocationHandler.java:57)
	at com.sun.proxy.$Proxy64.actionPerformed(Unknown Source)
	at java.desktop/javax.swing.AbstractButton.fireActionPerformed(Unknown Source)
	at java.desktop/javax.swing.AbstractButton$Handler.actionPerformed(Unknown Source)
	at java.desktop/javax.swing.DefaultButtonModel.fireActionPerformed(Unknown Source)
	at java.desktop/javax.swing.DefaultButtonModel.setPressed(Unknown Source)
	at java.desktop/javax.swing.plaf.basic.BasicButtonListener.mouseReleased(Unknown Source)
	at java.desktop/java.awt.Component.processMouseEvent(Unknown Source)
	at java.desktop/javax.swing.JComponent.processMouseEvent(Unknown Source)
	at java.desktop/java.awt.Component.processEvent(Unknown Source)
	at java.desktop/java.awt.Container.processEvent(Unknown Source)
	at java.desktop/java.awt.Component.dispatchEventImpl(Unknown Source)
	at java.desktop/java.awt.Container.dispatchEventImpl(Unknown Source)
	at java.desktop/java.awt.Component.dispatchEvent(Unknown Source)
	at java.desktop/java.awt.LightweightDispatcher.retargetMouseEvent(Unknown Source)
	at java.desktop/java.awt.LightweightDispatcher.processMouseEvent(Unknown Source)
	at java.desktop/java.awt.LightweightDispatcher.dispatchEvent(Unknown Source)
	at java.desktop/java.awt.Container.dispatchEventImpl(Unknown Source)
	at java.desktop/java.awt.Window.dispatchEventImpl(Unknown Source)
	at java.desktop/java.awt.Component.dispatchEvent(Unknown Source)
	at java.desktop/java.awt.EventQueue.dispatchEventImpl(Unknown Source)
	at java.desktop/java.awt.EventQueue$4.run(Unknown Source)
	at java.desktop/java.awt.EventQueue$4.run(Unknown Source)
	at java.base/java.security.AccessController.doPrivileged(Native Method)
	at java.base/java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(Unknown Source)
	at java.base/java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(Unknown Source)
	at java.desktop/java.awt.EventQueue$5.run(Unknown Source)
	at java.desktop/java.awt.EventQueue$5.run(Unknown Source)
	at java.base/java.security.AccessController.doPrivileged(Native Method)
	at java.base/java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(Unknown Source)
	at java.desktop/java.awt.EventQueue.dispatchEvent(Unknown Source)
	at java.desktop/java.awt.EventDispatchThread.pumpOneEventForFilters(Unknown Source)
	at java.desktop/java.awt.EventDispatchThread.pumpEventsForFilter(Unknown Source)
	at java.desktop/java.awt.EventDispatchThread.pumpEventsForHierarchy(Unknown Source)
	at java.desktop/java.awt.EventDispatchThread.pumpEvents(Unknown Source)
	at java.desktop/java.awt.EventDispatchThread.pumpEvents(Unknown Source)
	at java.desktop/java.awt.EventDispatchThread.run(Unknown Source)
Caused by: org.python.core.PyException: encodings.CodecRegistryError: incompatible codecs in module "encodings.hex_codec" (C:\Users\aedmw\.ignition\cache\gwlocalhost_8088\C0\pylib\encodings\hex_codec.py)
	... 102 common frames omitted

PGriffith · January 22, 2024, 11:00pm

This is fixed in 8.1.36.

Daniel_Webb · January 23, 2024, 6:11pm

Is there a simple fix, like a diff of the pylib json files? I don't have administrative control of the Ignition servers I use and it is a lot of effort to upgrade versions because of Large Corporate Inertia.

PGriffith · January 23, 2024, 6:16pm

Actually, yes, in this case it's an easy fix - patch your codecs.py file in the pylib directory on your gateway to make the Codec class a "new-style" class.
That is, change the file like this:

@@ -89,7 +89,7 @@
     def __repr__(self):
         return "<%s.%s object for encoding %s at 0x%x>" % (self.__class__.__module__, self.__class__.__name__, self.name, id(self))
 
-class Codec:
+class Codec(object):
 
     """ Defines the interface for stateless encoders/decoders.

Exact line numbers will vary a little bit depending on what version of Ignition your system started out on.
Making that change on the gateway's filesystem should automatically disseminate changes to your designers and clients.

See jython 2.7.x: CodecRegistryError during attempt to use 'json' or 'codecs' module · Issue #96 · jython/jython · GitHub for more details.

Daniel_Webb · January 23, 2024, 8:38pm

Thanks so much! Worked like a charm.